{
    type Stu = {
        name: string,
        age: number
    }
    let s1:any = {name: 'xx', age: 18}

    s1.c = 100

    let str:any = 'abc'
    str = 100

    // 定义一个函数，传入数据，返回类型
    function getType(s:any) :string{
        return 'string'
    }

    getType('1')

    let a;
    function f1(a){
        
    }
}